Core box with sectional mold construction



Sept; 1959 J. G. co vrr-r 2,901,792

CORE BOX WITH SECTIONAL MOLD CONSTRUCTION 4 sheets sheet 1 Filed April 28, 1958 lHHHIIII H.

I N VENTOJ? Jack 6. Cor/177 .QHQENEV Sept. 1, 1959 J. G. COVlTT 2,901,792

CORE BOX WITH SECTIONAL MOLD CONSTRUCTION Filed April 28, 1958 4 Sheets-Sheet 2 17v VENTOE L/iacr G. Gov/r1 QILQO'M S p 1, 1959 J. G. covn'T 2,901,792

CORE BOX WITH SECTIONAL MOLD CONSTRUCTION Filed A ril 28, 1958 4 Sheets-Sheet 3 Z'NVENTOE /4CK 6. Co 1/127 Sept. 1, 1959 J. G. COVITT 2,901,792

CORE BOX WITH SECTIONAL-MOLD CONSTRUCTION Filed April 28, 1958 v 4 Sheets-Sheet 4 INvEA/roz? 1J4 CA G (201/1 17 411-0 ENE)! United States Patent CORE BOX WITH SECTIONAL MOLD CONSTRUCTION Jack G. Covitt, Fort Wayne, Ind., assignor to International Harvester Company, Chicago, 111., a corporation of New Jersey Application April 28, 1958, Serial No. 731,214

7 Claims. (Cl. 22- 13) This invention relates to core boxes and more particularly to a core box having a sectional mold. More specifically the invention relates to a core box for making cores utilized in the casting of bladed articles.

In the manufacture of torque converter castings, the cores for making the bladed portions of pumps and other components play an important part. The cores utilized in the casting of these parts generally are made of a plaster type material which has excellent non-shrinking and non-expansion characteristics. This is decidedly important in that the blades of the converter components should all be of the same thickness within close tolerances. Thus in the manufacture of cores it is extremely important to provide a core box which will permit the cores to be manufactured expeditiously and within close tolerance limits. Components of the core box must be closely machined and it is exceedingly important to provide expeditious means whereby the cores may be removed from the core box without any likelihood of damage to the core. Cores of the plaster type are extremely frangible and thus the standard type of box has not proved satisfactory. Furthermore, cores for making converter blades, by virtue of their unusual curvature, ordinarily are difficult to remove from the conventional type core box without damage to the cores. It is thus a prime object of this invention to provide an improved core box which will permit the manufacture of plaster type cores whereby the cores can be accurately held within close tolerance limits.

A still further object is the provision of an improved core box wherein cores can be expeditiously manufactured and can readily be removed after the cores have hardened.

A still further object is the provision of an improved core box including a plurality of separable mold elements which may be moved to and from a closed position during the manufacture of plaster type cores.

Still another object is the provision of an improved core box having a separable mold assembly, the said mold assembly being readily separable with certain components of the box for permitting the ready removal of the finished core from the box.

A further object is the provision of an improved core box for making cores utilized in the manufacture of torque converter pump blades, the said core box including a separable mold construction and adjustable means whereby more than one size core may be manufactured.

These and further objects will become more readily apparent from a reading of the specification when exam- Figure 5 is a side view partly in elevation of a core box assembly, the said view also having portions broken away to show the interior arrangement of the core box;

Figure 6 is a front elevational view of the core box assembly; and

Figure 7 is a perspective view of a core produced in the core box shown in Figures 1 through 6.

Referring now particularly to Figures 1 through 3 a core box is generally designated by the reference character 10, the said box comprising a base 11 having an upright support 12 suitably connected to the said base 11. The support 12 includes a bore 13, and a second enlarged bore 14 communicating with the bore 13. A pair of collars 15 and 16 are positioned on the support 12 in superposed relation. The collar 15 is provided with a bore 17 and the collar 16 is provided with a bore 17 of substantially the same diameter as the bore 14. A pin 18 has an enlarged head portion 19 which is seated in flush relation within a bore 19' of the collar 15. The pin 18 includes a body 20 seated within the bores. 14, 17 and 17, the said body having a reduced end portion 21 disposed within the bore 13 of the support 12.

A pair of vertical side members or upri ht plates 22 and 23 are positioned on the base 11 in relatively V-shaped arrangement. The vertical side member 22 is suitably connected to the collar 16 by means of a plurality of screws 22' and the vertical side member 23 is also similarly connected to the collar 15 by means of a plurality of screws 23. A pair of handles 24 are suitably connected to the side members 22 and 23 so that the side members 22 and 23 may be hingedly moved with the collars 15 and 16 on the pin 13. Thus the collars 15 and 16 are free to pivot on the pin 18 and the side plates 22 and 23 may be swung from a closed to an opened position as particularly Well disclosed in Figure 3.

A mold, generally designated at 25, is positioned forwardly of the support 12. The mold 25 is a sectional type mold consisting of a plurality of sections which will hereinafter be described. The sectional mold 25 is suitable for manufacturing frangible core members of the type shown in Figure 7, the said core member disclosed being generally referred to by the reference character 26. The type of core 26, shown in Figure 7, is utilized in a casting operation for producing torque converter castings (not shown). In the pump, for instance, of a torque converter, a casing is provided with a plurality of radially extending relatively thin vanes or blades. In order to cast the blades in position it is necessary to first produce cores of the type shown in Figure 7. In the manufacture of the mold, which is utilized in the casting operation, the individual cores 26 are placed in circumferentially adjacent relation, having side faces slightly spaced, the: said spaces providing the blades in the finished casting. As heretofore stated it is extremely necessary that the cores be manufactured of close tolerances so that the resultant castings will be accurate. The material used in the cores is of course quite important and need not be further elaborated upon. Generally a type of plaster mix is utilized.

The core 26, comprises generally, an arch-shaped body 27 having an outer convex surface 28 and an inner concave surface 29. A connector 30 is integral with the body 27, the connector 3% having at one end a dovetail slot 31.

As best shown in Figure 3 a first mold section 32 comprises a concavity 33 and an upright end wall 34 having an inner curved surface 34'. The first mold section 32 is suitably firmly supported on the base 11 by suitably securing means, not shown.

, A second mold section 35 comprises a body 36, and an inner concave surface 37, and an outer convex surface 38. It can be seen that the mold section 35 is of generally the same shape as the core 26. A third rhold section is designated at 39, the said mold section 39 being of the same general shape as the second mold section 35 and the core 26. The third mold section 39 comprises a body 40 having a concave surface 41 and a convex surface .2. The mold sections 35 and 39 include side surfaces 44 and 45 which in the closed position of the side members 22 and 23 provide a cavity for producing the core 26. The mold sections 35 and 39 are suitably connected to the side members 22 and 23 by means of screws 42 and 43.

A support 46 is rigidly connected to the base 11, adjacent the rear of the support 12. An L-shaped arm 47 is pivotally connected to the support 46 by means of a pivot pin 48. A bracket 49 is suitably connected, as indicated at St), to a fourth mold section 51, the said bracket 49 being pivotally connected to the arm 47 by means of a pivot pin 52.. The fourth mold section 51 comprises a convex surface 53 which is adapted to seat upon and conform to the concavity 33. The third mold section 39 also has a projection 54 connected thereto for movement with the vertical plate 23. The ends of the vertical plates 22 and 23 are provided with inserts 55, which as best shown in Figures 1, 2 and 4, are adapted to engage stop members 56. Each stop member 56 includes a pin 57 which is in mating relation with respect to a bore 58, the said bores 58 being laterally spaced whereby the stops 56 are disposed between the vertical plates 22 and 23. As shown in Figure 3 the base 11 also includes bores 58' disposed outwardly of the stops 56 shown, the said latter bores 58' also being engageable by the pins 57 so that the stops may be adjusted outwardly if desired. Immediately adjacent the stops 56, and outwardly with respect thereto, a pair of earns 59 are provided. The cam members 59 are suitably pivoted as indicated at 60 on the base 11, the said cam members 59 including handles 61. The cam members 59 are so designed that when the vertical members 22 and 23 are swung to the closed position shown in Figures 1, 2 and 4, that they will engage the said members 22 and 23 to securely lock the same against the stops 56. By merely turning the cams 59 the cam edges, which normally lock the members 22. and 23 in a closed position, will move to a position so that the members 22 and 23 can readily move outwardly to the position shown in Figure 3.

In the operation, referring now to Figure 2, the side members 22, and 23 have been moved into a closed position. In this position the side surfaces 44 and 45 f the mold sections 35 and 39 are positioned in laterally spaced relation to provide a mold cavity. The convex surfaces 33 and 42 nest in the concavity 33, the said nesting being with relatively small tolerances between the surfaces. The cam members 59 are positioned to lock the side members 22 and 23 in the closed position. In Figure 2 the fourth mold section 51 is in a raised position and this mold section is now lowered so that the convex surface 53 nests in the concave surfaces 37 and 41 forming in effect a bridge and top cover over the mold cavity. As shown in Figure 2 the projection 54 is also now in position. Thus the sectional mold 25 is now positioned properly within the core box as shown in Figure l and liquefied material such as liquefied plaster may be poured through and into a space designated at A in Figure 1, the said space being formed by the spaced relation of the mold sections 35 and 39. After the cavity has been filled it is a simple matter to smooth out the surface of the plaster flush with the upper end of the opening A and upon hardening of the plaster the cam members 59 are rotated so that the side plates 22 and 23 can be moved to the open position. Also previous to movement of the plates 22 and 23, the mold section 51 is raised again to the position shown in Figure 3. The core 26 can now quite easily and readily be removed from the core box without any possibility of damage dining such removal.

The arrangement of the core box shown is such that all Of the surfaces of the mold are held to Close tolerances. Accurate core manufacture is thus obtained and easy removal of the core is assured. In order to make a re1atively wider core it is a simple expedient to move the stops 56 outwardly into the bores 58 whereupon the identical arrangement may be utilized to elfectua'te a wider core.

Thus it is obvious that an improved core box arrangement has been described which fully accomplishes the novel objects of the invention. It is of course realized that changes and modifications may be made which do not depart from the spirit of the invention as disclosed or the scope thereof as defined in the appended claims.

What is claimed is:

1. A core box for making cores utilized in the casting of bladed articles, each core including a body having an outer convex surface and an inner concave surface; said core box comprising a base, first and second vertical side members supported on said base, means hingedly connecting said side members to said base for hinging movement about a vertical axis, a mold supported on said base including a first mold section having a first concavity and an end wall having a vertically extending curved inner surface, second and third mold sections respectively connected to said first and second side members, said second and third mold sections having generally the shape of a finished core including an outer convex surface and an inner concave surface, said second and third mold sections being movable inwardly with said side members from an open position to a closed position whereby said outer convex surfaces of said second and third mold sections nest with respect to said first concavity and the concave surface of said second and third mold sections provide a second concavity, an arm hingedly connected to said base for pivotal movement about a horizontal axis, a bracket hingedly connected to said arm about a horizontal axis, a fourth mold section connected to said bracket, said fourth mold section having a convex surface, said arm, bracket, and fourth mold section being hingedly movable to a closed position whereby the convex surface of said fourth mold section nests with respect to said second concavity and said fourth mold section is disposed in said second concavity, laterally spaced adjustable stop members between said side members adapted to be engaged by said side members to limit the inward movement of said second and third mold sections whereby they are laterally spaced to provide with said first mold section a mold cavity, and a pair of cam elements on said base adapted to lock said side members in the closed position.

2. A core box for making cores utilized in the casting of bladed articles, each core including a body having an outer convex surface and an inner concave surface; said core box comprising a base, first and second vertical side members supported on said base, means hingedly connecting said side members to said base for hing'ing movement about a vertical axis, a mold supported on said base including a first mold section having a first concavity, second and third mold sections respectively connected to said first and second side members, said second and third mold sections having generally the shape of a finished core including an outer convex surface and an inner concave surface, said second and third mold sections being movable inwardly with said side members from an open position to a closed position whereby said outer convex surfaces of said second and third mold sections nest with respect to said first concavity and the concave surface of said second and third mold sections provide a second concavity, an arm hingedly connected to said base for pivotal movement about a horizontal axis, a bracket hingedly connected to said arm about a horizontal axis, a fourth mold section connected to said bracket, said fourth mold section having a convex surface, said arm, bracket, and fourth mold section being hingedly movable to a closed position whereby the convex surface of said fourth mold section nests with respect to said second concavity and said fourth mold section is disposed in said second concavity, laterally spaced adjustable stop members between said side members adapted to be engaged by said side members to limit the inward movement of said second and third mold sections whereby they are laterally spaced to provide with said first mold section a mold cavity, and a pair of cam elements on said base adapted to lock said side members in the closed position.

3. A core box for making cores utilized in the casting of bladed articles, each core including a body having an outer convex surface and an inner concave surface; said core box comprising a base, first and second vertical side members supported on said base, means hingedly connecting said side members to said base for hinging movement, a mold supported on said base including a first mold section having a first concavity, second and third mold sections respectively connected to said first and second side members, each of said second and third mold sections having generally the shape of a finished core including an outer convex surface and an inner concave surface, said second and third mold sections being movable inwardly with said side members from an open position to a closed position whereby said outer convex surfaces of said second and third mold sections nest with respect to said first concavity and the concave surface of said second and third mold sections provide a second concavity, an arm hingedly connected to said base for pivotal movement about a horizontal axis, a fourth mold section connected to said arm, said fourth mold section having a convex surface, said arm, and fourth mold section being hingedly movable to a closed position whereby the convex surface of said fourth mold section nests with respect to said second concavity and said fourth mold section is disposed in said second concavity, laterally spaced adjustable stop members between said side members adapted to be engaged by said side members to limit the inward movement of said second and third mold sections whereby they are laterally spaced to provide with said first mold section a mold cavity, and means on said base adapted to lock said side members in the closed position.

4. A core box for making cores utilized in the casting of bladed articles, each core including a body having an outer convex surface and an inner concave surface, said core box comprising a base, first and second vertical side members supported on said base, means hingedly connecting said side members to said base for hinging movement about a vertical axis, a mold supported on said base including a first mold section having a first concavity and an end wall having a vertically extending curved inner surface, second and third mold sections respectively connected to said first and second side members, said second and third mold sections having generally the shape of a finished core including an outer convex surface and an inner concave surface, said second and third mold sections being movable inwardly with said side members from an open position to a closed position whereby said outer convex surfaces of said second and third mold sections nest with respect to said first con cavity and the concave surfaces of said second and third mold sections provide a second concavity, an arm hingedly connected to said base for pivotal movement about a horizontal axis, a fourth mold section connected to said arm, said fourth mold section having a convex surface, said arm and fourth mold section being hingedly movable to a closed position whereby the convex surface of said fourth mold section rests with respect to said second concavity and said fourth mold section is disposed in said second concavity laterally spaced adjustable stop members between said side members adapted to be engaged by said side members to limit the inward movement of said second and third mold sections whereby they are laterally spaced to provide with said first mold section a mold cavity, and means on said base adapted to lock said side members in the closed position.

5. A core box for making cores utilized in the casting of bladed articles; said core box comprising a base, first and second vertical side members supported on said base, means hingedly connecting said side members to said base for hinging movement about a vertical axis, a mold supported on said base including a first mold section, second and third mold sections respectively connected to said first and second side members, each second and third mold sections including an outer surface and an inner concave surface, said second and third mold sections being movable inwardly with said side members from an open position to a closed position whereby said outer surfaces of said second and third mold sections are disposed over said first mold section to provide a second concavity, an arm hingedly connected to said base for pivotal movement, a fourth mold section connected to said arm, said fourth mold section having a convex surface, said arm and fourth mold section being hingedly movable to a closed position whereby the convex surface of said fourth mold section nests with respect to said second concavity and said fourth mold section is disposed in said second concavity, and means on said base adapted to be engaged by said side members to limit the inward movement of said second and third mold sections whereby they are laterally spaced to provide with said first mold section a mold cavity.

6. A core box for making cores comprising a base, a pair of side members hingedly mounted on said base, said side members being movable toward each other to a closed position and away from each other to an open position, a four piece mold including a first mold section rigidly supported on said base, second and third mold sections respectively positioned on said first and second side members for movement therewith, a fourth mold section, means hingedly supporting said fourth mold section on said base whereby said fourth mold section may be raised and lowered, stop elements adjustably supported on said base between said side members, said stop elements limiting the inward movement of said side members whereby said second and third mold sections are spaced to form with said first mold section a mold cavity, said fourth mold section being movable to a closed position to provide a top closure for said mold cavity, said second, third and fourth mold sections being movable from the closed position whereby a molded core may be removed from said mold.

7. A core box for making cores comprising a base, a pair of side members movably mounted on said base, said side members being movable toward each other to a closed position and away fromeach other to an open position, a sectional mold including a first mold section rigidly supported on said base, second and third mold sections respectively positioned on said first and second side members for movement therewith, a fourth mold section, means movably supporting said fourth mold section on said base whereby said fourth mold section may be moved, stop elements adjustably supported on said base between said side members, said stop elements limiting the inward movement of said side members whereby said second and third mold sections are spaced to form with said first mold section a mold cavity, said fourth mold section being movable to a closed position to provide a top closure for said mold cavity, said second, third and fourth mold sections being movable from the closed position whereby a molded core may be removed from: said mold.

References Cited in the file of this patent UNITED STATES PATENTS 

